Tape feeding apparatus



Dec. 22, 1964 J. H. M. GALLARD ETAL TAPE FEEDING APPARATUS 5 Sheets-Sheet 1 Filed July 6, 1962 \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\&

Dec. 22, 1964 J. H. M. GALLARD ETAL 3,152,345

TAPE FEEDING APPARATUS Filed July 6, 1962 5 Sheets-Sheet 3 II II ll ll llfl Dec. 22, 1964 J. H. M. GALLARD ETAL 3,162,345

TAPE FEEDING APPARATUS Filed July 6, 1962 5 Sheets-Sheet 4 WWW ijm/zzzzzzzzzzzzzzzzz/zzzummm ZZMZZZZMZMZZMMMMMZ/ WWWW ARD ETAL 3,162,345

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5 Sheets-Sheet 5 United States Patent Ofifice 3,162,345 Patented Dec. 22, 1964 868, 4 Claims. (Cl. 226-95) The present invention relates to pneumatic tape-driving apparatus.

The apparatuses hitherto employed to drive a tape by pneumatic action generally comprise a rotor rotatable continuously about a stator which is provided in its periphery with a cavity closed by the rim of the rotor in such manner as to form a distribution chamber. The distribution chamber communicates through a valve either with a suction chamber or with a pressure chamber so as to apply suction or pressure, depending upon circumstances, through the apertures in the rim for the purpose of rendering possible or preventing the driving of the tape by the rotor of the apparatus.

The application of pressure, or suction, to apertures in the rim as a result of the operation of a valve takes place with some time lag depending upon the time taken to subject to suction or pressure the volume of air which is present in the device between the valve and the apertures in the rim. This time lag limits the degree of the acceleration to which the tape can be subjected by the driving apparatus.

In some known apparatus, this time lag has been reduced by reducing the volume of the distribution chamber and disposing the valve in the stator in the immediate neighbourhood of said chamber.

According to the invention, it is possible further to reduce this time lag by omitting the distribution chamber. The pressure chamber and the suction chamber are then disposed in the periphery of the stator along the rim and a closure device is provided between the inner face of the rim and the periphery of the said chambers and is so arranged as to place the apertures in the rim selectively in communication with the pressure chamber or with the suction chamber.

In accordance with one embodiment of the invention, the closure device comprises a grid so arranged as to take up either of two active positions in relation to the stator under the action of a control device. According to the active position occupied by said grid, peripheral apertures in the pressure chamber are placed in communication, through apertures in the grid, with apertures in the rim which come into alignment therewith in the course of the rotation of the rotor, or are closed by imperforate portions of the grid, while peripheral apertures in the suction chamber are closed by imperforate portions of the said grid or are placed in communication through apertures in the grid with apertures in the rim which come into alignment therewith in the course of the rotation of the rotor.

In accordance with a modified embodiment of the invention, the closure device comprises a grid rotatable with the rotor and so arranged as to occupy, under the action of a control device, either of two active positions in relation to the rotor. Depending upon the active position occupied by the said grid,fapertures in the rim which come into alignment with peripheral apertures in the pressure chamber during the rotation of the rotor are aligned with apertures in the grid, 01' are closed by imperforate portions in the latter, while apertures in the rim which come into alignment with peripheral apertures in the suction chamber in the course of the rotation of the rotor are closed by imperforate portions, or they are aligned with apertures in the grid.

For a better understanding of the invention and the manner in which it may be performed, the same will now be described, by way of example withreference to the accompanying drawings, in which:

FIGURE 1 is a vertical sectional view through an apparatus according to a first embodiment of the invention, the section being taken along the axis of rotation of a rotatable part of the apparatus,

FIGURE 2 is a vertical sectional view along the line 22 of FIGURE 1,

FIGURES 3a and 3b are views of a detail of an enlarged portion of FIGURE 1.

FIGURES 4a, 4b and 4c illustrate planar developments of certain cylindrical elements of the apparatus according to the first embodiment of the invention,

FIGURE 5 is a vertical sectional view similar to FIG- URE 1, through apparatus according to a second embodiment of the invention,

FIGURE 6 is a vertical sectional view along the line 66 of FIGURE 5, and

FIGURES 7a, 7b and 7c are planar developments of certain cylindrical elements of the apparatus according to the second embodiment of the invention.

The tape driving apparatus illustrated in FIGURES 1 and 2 comprises a rotor 10, a stator 20, a closure device 30 and a motor 40 which controls the closure device 30.

The rotor 10 comprises a hub 101, a rim 11 and a web 15 connecting the hub to the rim on one side of the rotor. The rim 11 has formed in its periphery a circular groove, the base of which is formed with apertures 12 in the form of slots parallel to the axis of rotation of the rotor. The said apertures lead to the inner face of the rim. The edges 13 of the groove serve to guide the tape 50. The rotor 10 is keyed on a shaft 100, which is continuously rotated by appropriate means (not shown).

The stator 20 fixedly connected to the frame 200 of the apparatus is disposed along a portion of the inner face of the rim 11 of the rotor. In FIGURE 2, it will be seen that the tape 59 which is to be driven by the device is wound around a portion of the rim situated within an angle A. The stator is hollow and forms a pressure chamber 21 and a suction chamber 22.

As may be seen from FIGURE 2, the pressure chamber 21 extends along that portion of the rim which is situated within the angle A and contains the suction chamber 22, which extends only along that portion of the rim which is situated within the angle B, which is smaller than the angle A.

As may be seen from FIGURES 1, 3a and 3b, the pressure chamber 21 extends, in parallel relationship to the axis of rotation of the rotor, only along the edges of the groove 11, The Wall 23 of said chamber along the rim of the rotor is formed with apertures 230.

As may be seen from FIGURE 1, the suction chamber 22 extends, in parallel relationship to the axis of rotation of the rotor, only along the central portion of the groove 11. The wall 24 of said chamber along the rim of the rotor is formed with apertures 240.

The pressure chamber 21 is connected by a pipe 25 to a compressor (not shown) and is maintained by the latter at a superatmospheric pressure.

The suction chamber 22 is connected by a pipe 26 to a vacuum pump (not shown) and is maintained by the latter at a subatmospheric pressure.

The closure member 30 comprises a grid 31 disposed between the walls 23 and 24, on the one hand, and the rim 11 on the other hand. The grid 31 is adapted to slide in a direction parallel to the axis of rotation of the rotor so as to pass from one of its two active positions a rectilinear reciprocating movement.

3 illustratedin FIGURES 3a and 3b to the other. It may be controlled by any driying device capable of producing An electromagnet designed, for example, in a manner similar to that of a driving member of an. electrodynamic loudspeaker,-conforms to this condition and, in addition, makes it possible to produce highlinear speeds by reason of its low inertia.

The grid 31 is rigidly conected by the rod 35 'to the coil 41 of such a driving member 40.

The control circuit of the electromagnet must supply a current of high strength only during the period of move'ment of the grid. The grid, can be maintained'in eachof its active positions by a current. of much lower strength. a

The grid' 31 is so guided as to slide without'friction between the rim 11 of the rotor and the Walls 23 and 24' of thepressure and suction chambers. This ensures I longer useful life of the apparatus.

.As may be seen from FIGURES 3a and 3b, the dimeru sions. parallel to the axis of rotation of the rotor, of, the apertures 310 in the grid31 and of the apertures 230,- 240 in the Walls 23 and '24 are equal to one another andatsmost equal to the dimensions, in the'direction parallel to the same axis, of the imperforate portions .r

211,,311ofthe said elements. In addition, the apertures and'the imper for'a'te portions ofthe grid 31 andpdfjthe walls 23 and 24 are 50 arranged that if thefgrid is situated in its active position to theleft, as shownin FIGURE 3a,

its apertures 310 are aligned with the apertures 230 in the wall 23 and its i'mperforate portions 311 close the apertures 240 in the wall 24, and in such manner that if the grid is in its active position to the right, as shown in FIGURE 311, its imperfo'rate portions 311 close the walls 23 and 24 of the apparatus v embodiment of, the invention. These'fi'gures show the on an armature "tion. I

through the angle B and ceases to adhere thereto as soon as it leaves the angle B so as to leave it as soon as it emerges from the angle A.

The foregoing description relates to one particular embodiment of the invention. FIGURES 5, 6, 7a, 7b and 7c illustrate another embodiment of-the invention. In accordance with this embodiment, theclosure device is so arranged as to pivot about the axis of the rotor instead of sliding in parallel relationship to that axis.

This embodiment of the invention utilisesa stator and a rotor which are substantially identical to those previously descrihed. Theclosure device comprises a grid 31 connected to a sleeve 32 by a recessed cheek 33. The'l sleeve 3'2 is so mounted as to be able to pivot on thatportion of thestator which forms therbeari'ng surface "'27. The. closure device caniflthus pivot about the axis of rotation of the rotor so as to pass from one of its active positions to the other, and it is driven byan electromagnet 43 'acting, aga inst the action of a return spring44, 45 fixed to the sleeve32 in 'aradial posi- FIGURES 7a, .7b and. 7c illustrate respectively plane developments of the rim 1 1, of the "grid'31 and a of the according to this second shape and the relative posit'ioning of the, apertures of the said elements. This shape rind-thisrelative positioning apertures 230 "in the Wall '23 and its apertures 310 are" I aligned withth'e apertures 240 in the Wall24. The shape and location of the apertures hereinbefor'e referr'etlto illustrate plane developments of the rim 11., of the grid 31 and of thefwalls23 and 24 respectively. Whe'n'the .grid is situated-in the position illustrated in .FlGUREea,

the pressure obtained in the chamber 21 is appli'ed to the in spaced relationship to 'the base of the groove in the rotor. Under thesec'ondi'tions, the tape cannot be driven the 'rotor. Whenftheg'rid is situated in't'he' position illustrated in FIGURE 3b,thesuction obtaining in the' chamber "22 is imparted 'tothe aperturesinthe firm which are clearly apparent from FIGURES 4a, 4b and 4c'which are also suitablefor the apparatus according to the first embodiment of'the invention.

It is tov be understood thatthe invention is notlimit'ed to the shapes andpositionings of the apertures as indicated in the, present description, and in general the invention is also not limited to the particular embodiments which have been described in the foregoing. Thus, the closure device may, in accordance with amod ified em- "fbodimen't of the invention, be mounted onthe rotor in such manner as to rotate therewith and tooccupy'selee tively, under the action of a control device, either of two active positions on'the'said rotor.v closure device,

depending upon its active position on the rotor, masks 'or unmasks apertures in the rim which, in the course of are situated within the angle .B (FIGURE 2) and, in this angle, maintains the tape applied against the base of the, groove in the rotor. The tape is then driven by the rotor. The change of the grid from one position to the other must instantaneously start or stop the tape.

volume of air to which thepressu're or suctionis to be appliedatjeach operation of the gridis limitedto thatfl "of the apertures in the grid and to that of the effective apertures in the rim, the latter-[apertures being at a 'give'ninstant, those which travelpast the apertures in the grid at this "instant; I

ltwill be seenffrom rdulifii that 'thesuetioii charnber 22 is situated along the longitudinal axis of the tape, so that at the instant when this chamber is placed in com-. munication with ,the apertures in. the rim, the suction is set up from theinside towards the outside.

-It will, be seen iro'miFIGURE 2 that a portion. offth e wall 23 I of thepressure chamber 21 is situated outside the angle B. Apertures231 in this part of the .Wall 23 1 1 continuously coincide'with apertures in the grid 31 regardlessfof the positionofthe -latter,'-so that during the driyw ing of the tape by the rotor, whenthe grid is situated 1n applied to the apertures in the rim. v v

the rotation of the rotor, cornerintoalignment with peripheraLapertures inxthe pressure chamber and simultarieo'us'ly 'unmasks or rnasks apertures in the rim which come into alignment with peripheral'apertur'es in the suction chamber.

@Finally, it is p o ssible in accordance with the invention to simplify the tape driving appanatusfl of the type *previously described by omitting the pressure chamber, it

having been found'that under some conditions the tape leaves the rotor even ifno superatmospheric pressure is W m?,.' r g 7 1. A tape feeding 'apparatus comprising a rotor co'nstituted of a rotatableshell mounted on a rotating shaft and having a cylindricalirim Withjari exterior surface and an interiorisurface, said cylindrical rim being pro- ,jlmunication of. air-between said exterior surface and said vided with radially extending aperture whi'challdw corn- 1 interior surface, a stator disposed within said. shell and "provided with a pressure chamber and a suction chamber said chambers .beirlgl separated from each other by a partition disposed.perpendicularly to -the :fiXis of said shaft, said 'char nber's being peripherally limited by a' thin wvall hav'ng a cylindrical outer side located inside said the position indicated in FIGURE 311," the apertures in 1the"'r'in1, which are subjected 'to su'ction during their pas f "j sage through the a'ngle B, :are subjected to a pressure ap} plied through thesaid apertures 23 1 inthe wall 23 when they leave this angle while turning in the direction-of 1 nie'ansfr" respect being pro (1 ri'nr at a small radial; distance or the interior surface of saidirinnrwithin such Ttape-corita'cting angle Within which the extetior ,Surfac i. said rimis contacting 1118' tape,

' 'urp yi as i'venes'ofisa "chambers, a'fir's'tgroup ofi,ports ed in's d 'wal-l v for-"allowing co'mrnunica- V ;tion of=-a between pressure chamber and iSBildOUtBI side ot'sa'id wallga second group' of-ports being provided neurn'atic pressure and suction to a in said wall for allowing communication of air between said suction chamber and said outer side of said wall, and an air distributing means including an arcuate thin plate located between said outer side of said wall and the interior surface of said rim, said arcuate plate being adapted to occupy either a first or a second operating position and being provided with a first group of openiugs which register with the ports of said first group of ports in said wall while imperforate portions of said arcuate plate cover the ports of said second group of ports when said arcuate plate occupies its first operating position, said arcuate plate being further provided with a second group of openings which register with the ports of said second group of ports in said wall while imperforate portions or said arcuate plate cover the ports of said first group of ports when said arcuate plate occupies its second operating position, whereby, according to whether said arcuate plate occupies its first or its second operating position, either said pressure chamber or said suction chamber is placed in communication with portions of said exterior surface or" the rim passing through said tape-contacting angle, said tape feeding apparatus further comprising an electrically controlled actuator mechanically connected to said arcuate plate for shifting said arcuate plate from one of its operating positions to the other and vice versa.

2. A tape feeding apparatus according to claim 1, wherein said pressure chamber comprises two parts circumferentially extending along said wall on either side of said suction chamber, ports of said first group of ports being distributed in two axially spaced circumferentially extending areas of said wall, and the second group of ports being located in a central area of said wall intercalated between said two axially spaced areas, whereby suction is set up from the longitudinal axis towards the edges of that portion of the tape which is located within said tape-contacting angle at the instant when the suction chamber is placed in communication with portions of said rim passing through the tape-contacting angle as a result of the valve being shifted to its second operating position by the electrically controlled actuator.

3. A tape feeding apparatus according to claim 2, wherein said pressure chamber comprises a part linking said two circumferentially extending parts along said wall, said linking part being located behind said suction chamber in the direction of rotation of the rotor, ports of said first group of ports being located in an area of said Wall linking said two axially spaced areas, said linking area being located behind said central area in the direction of rotation of the rotor and being permanently in communication with said interior surface of the rim, whereby during the driving of the tape by the rotor, when the plate of said air distributing means occupies its second operating position, that portion of the tape which adheres to the rotor during its passage over the suction chamber, ceases to adhere to the rotor and is thrust away during its passage over the linking part of the pressure chamber.

4. A tape feeding apparatus comprising a rotor constituted of a rotatable shell mounted on a rotating shaft and having a cylindrical rim with an exterior surface for engaging said tape and an interior surface, said rim being provided with a plurality of elongated apertures extending between said exterior surface and said interior surface thereof, a stator disposed within said shell and comprising a pressure chamber and a suction chamber, said chambers being separated from each other by a partition disposed perpendicularly to the axis of said shaft, said chambers being peripherally limited by an arcuate thin Wall parallel to the interior surface of said rim and extending angularly within the contacting portion of the tape with the exterior surface of said rim, a first group of ports being provided in said wall for allowing communication of air between said pressure chamber and said outer side of said wall, a second group of ports being provided in said wall for allowing communication of air between said suction chamber and said outer side of said wall, and an air distributing means including an arcuate thin plate located between said outer side of said wall and the interior surface of said rim, said arcuate plate being able to occupy either a first or a second operative position and being provided with a first group of openings which register with the ports of said first group of ports in said wall while imperforate portions of said arcuate plate cover the ports of said second group of ports when said arcuate plate occupies its first operative position, said arcuate plate being further provided with a second group of openings which register with the ports of said second group of ports in said wall while imperforate portions of said arcuate plate cover the ports of said first group of ports when said arcuate plate occupies its second operative position, the dimensions, in a direction parallel to the axis of said shaft, of said ports and of said openings being equal to the dimensions, in a direction parallel to the axis of said shaft, of said imperforate portions of the arcuate plate, whereby, according to whether said arcuate plate occupies its first or its second operative position, either said pressure chamber or said suction chamber is placed in communication with portions of said exterior surface of the rim passing through said tape-contacting angle, said tape feeding apparatus further comprising an electrically controlled actuator mechanically connected to said arcuate plate for shifting said arcuate plate, in a. direction parallel to the axis of said shaft, from one of its operative positions to the other and vice versa.

References Cited by the Examiner UNITED STATES PATENTS 3,082,925 3/63 MacNeill et a1 a- 226 3,118,582 1/64 Rapoza 22695 SAMUEL -F. COLEMAN, Primary Examiner.

DAVID L. MOSELEY, RAPHAEL M. LUPO, ERNEST A. FALLER, 1a., Examiners. 

1. A TAPE FEEDING APPARATUS COMPRISING A ROTOR CONSTITUTED OF A ROTATABLE SHELL MOUNTED ON A ROTATING SHAFT AND HAVING A CYLINDRICAL RIM WITH AN EXTERIOR SURFACE AND AN INTERIOR SURFACE, SAID CYLINDRICAL RIM BEING PROVIDED WITH RADIALLY EXTENDING APERTURES WHICH ALLOW COMMUNICATION OF AIR BETWEEN SAID EXTERIOR SURFACE AND SAID INTERIOR SURFACE, A STATOR DISPOSED WITHIN SAID SHELL AND PROVIDED WITH A PRESSURE CHAMBER AND A SUCTION CHAMBER SAID CHAMBERS BEING SEPARATED FROM EACH OTHER BY A PARTITION DISPOSED PERPENDICULARLY TO THE AXIS OF SAID SHAFT, SAID CHAMBERS BEING PERIPHERALLY LIMITED BY A THIN WALL HAVING A CYLINDRICAL OUTER SIDE LOCATED INSIDE SAID RIM AT A SMALL RADIAL DISTANCE OF THE INTERIOR SURFACE OF SAID RIM, WITHIN SUCH TAPE-CONTACTING ANGLE WITHIN WHICH THE EXTERIOR SURFACE OF SAID RIM IS CONTACTING THE TAPE, MEANS FOR SUPPLYING PNEUMATIC PRESSURE AND SUCTION TO RESPECTIVE ONES OF SAID CHAMBERS, A FIRST GROUP OF PORTS BEING PROVIDED IN SAID WALL FOR ALLOWING COMMUNICATION OF AIR BETWEEN SAID PRESSURE CHAMBER AND SAID OUTER SIDE OF SAID WALL, A SECOND GROUP OF PORTS BEING PROVIDED IN SAID WALL FOR ALLOWING COMMUNICATION OF AIR BETWEEN SAID SUCTION CHAMBER AND SAID OUTER SIDE OF SAID WALL, AND AN AIR DISTRIBUTING MEANS INCLUDING AN ARCUATE THIN PLATE LOCATED BETWEEN SAID OUTER SIDE OF SAID WALL AND THE INTERIOR SURFACE OF SAID RIM, SAID ARCUATE PLATE BEING ADAPTED TO OCCUPY EITHER A FIRST OR A SECOND OPERATING POSITION AND BEING PROVIDED WITH A FIRST GROUP OF INGS WHICH REGISTER WITH THE PORTS OF SAID FIRST GROUP OF PORTS IN SAID WALL WHILE IMPERFORATE PORTIONS OF SAID ARCUATE PLATE COVER THE PORTS OF SAID SECOND GROUP OF PORTS WHEN SAID ARCUATE PLATE OCCUPIES ITS FIRST OPERATING POSITION, SAID ARCUATE PLATE BEING FURTHER PROVIDED WITH A SECOND GROUP OF OPENINGS WHICH REGISTER WITH THE PORTS OF SAID SECOND GROUP OF PORTS IN SAID WALL WHILE IMPERFORATE PORTIONS OF SAID ARCUATE PLATE COVER THE PORTS OF SAID FIRST GROUP OF PORTS WHEN SAID ARCUATE PLATE OCCUPIES ITS SECOND OPERATING POSITION, WHEREBY, ACCORDING TO WHETHER SAID ARCUATE PLATE OCCUPIES ITS FIRST OR ITS SECOND OPERATING POSITION, EITHER SAID PRESSURE CHAMBER OR SAID SUCTION CHAMBER IS PLACED IN COMMUNICATION WITH PORTIONS OF SAID EXTERIOR SURFACE OF THE RIM PASSING THROUGH SAID TAPE-CONTACTING ANGLE, SAID TAPE FEEDING APPARATUS FURTHER COMPRISING AN ELECTRICALLY CONTROLLED ACTUATOR MECHANICALLY CONNECTED TO SAID ARCUATE PLATE FOR SHIFTING SAID ARCUATE PLATE FROM ONE OF ITS OPERATING POSITIONS TO THE OTHER AND VICE VERSA. 